Half-lives of immunoglobulins IgG, IgA and IgM in the serum of new-born pigs.

Abstract

Half-lives of immunoglobulins IgA, IgG and IgM labelled with Iodine-125 were measured and compared with the half-lives of these immunoglobulins calculated from plasma levels during the first 2–3 weeks of life. The two methods gave similar results for IgG and IgA, but the mean IgM half-life calculated from plasma IgM levels was significantly longer than the mean half-life of IgM-I(125). IgM production and passage into the circulatory system during the first week of life could account for this difference.